#pragma once

#include "index.hpp"
#include "util.hpp"
#include <algorithm>
#include <jsoncpp/json/json.h>
#include<regex>
namespace ns_searcher
{
    struct InvertedElemPrint
    {
        InvertedElemPrint() : doc_id(0), weight(0) {}
        uint64_t doc_id;
        int weight;
        std::vector<std::string> words;
    };
    class Searcher
    {
    private:
        ns_index::Index *index; // 供系统进行查找的索引
    public:
        Searcher()
        {
        }
        ~Searcher()
        {
        }

    public:
        void InitSearcher(const std::string &input)
        {
            // 1.获取index对象
            index = ns_index::Index::GetInstance();
            // 2.根据index对象建立索引
            index->BuildIndex(input);
        }
        void Search(const std::string &query, std::string *json_string)
        {
            // 分词
            std::vector<std::string> words;
            ns_util::JiebaUtil::CutString(query, &words);

            // 触发
            // ns_index::InvertedList inverted_list_all;
            std::vector<InvertedElemPrint> inverted_list_all;
            // 解决重复的问题
            std::unordered_map<uint64_t, InvertedElemPrint> tokens_map;

            for (auto word : words)
            {
                boost::to_lower(word);
                ns_index::InvertedList *inverted_list = index->GetInvertedList(word);
                if (nullptr == inverted_list)
                {
                    continue;
                }
                // inverted_list_all.insert(inverted_list_all.end(), inverted_list->begin(), inverted_list->end());
                for (const auto &elem : *inverted_list)
                {
                    auto &item = tokens_map[elem.doc_id];
                    item.doc_id = elem.doc_id;
                    item.weight += elem.weight;
                    item.words.push_back(elem.word);
                }
            }
            for (const auto &item : tokens_map)
            {
                inverted_list_all.push_back(item.second);
            }
            // 合并排序
            // std::sort(inverted_list_all.begin(), inverted_list_all.end(), [](const ns_index::InvertedElem &e1, const ns_index::InvertedElem &e2)
            //           { return e1.weight > e2.weight; });
            std::sort(inverted_list_all.begin(), inverted_list_all.end(), [](const InvertedElemPrint &e1, const InvertedElemPrint &e2)
                      { return e1.weight > e2.weight; });
            // 构建
            Json::Value root;
            for (auto &item : inverted_list_all)
            {
                ns_index::DocInfo *doc = index->GetForWardIndex(item.doc_id);
                if (nullptr == doc)
                {
                    continue;
                }
                Json::Value elem;
                elem["title"] = doc->title;
                elem["desc"] = GetDesc(doc->content, item.words[0]);
                elem["url"] = doc->url;
                root.append(elem);
            }
            // Json::StyledWriter writer;
            Json::FastWriter writer;
            *json_string = writer.write(root);
        }
        std::string GetDesc(const std::string &html_content, const std::string &word)
        {
            const int prev_step = 50;
            const int next_step = 100;
            // 找到出现位置
            // 下面代码有bug
            //  std::size_t pos = html_content.find(word);
            //  if (pos == std::string::npos)
            //  {
            //      return "None";
            //  }
            auto iter = std::search(html_content.begin(), html_content.end(), word.begin(), word.end(), [](int x, int y)
                                    { return (std::tolower(x) == std::tolower(y)); });
            if (iter == html_content.end())
            {
                return "None";
            }
            int pos = std::distance(html_content.begin(), iter);
            // 获取star end
            int start = 0;
            int end = html_content.size() - 1;

            if (pos > start + prev_step)
                start = pos - prev_step;
            if (pos < end - prev_step)
                end = pos + next_step;
            // 截取字符串
            if (start >= end)
                return "None";
            std::string desc = html_content.substr(start, end - start);
            desc += "...";
            return desc;
        }
    };
}
